Characteristics of the Tsui Test and Pressure Waveform to Confirm Epidural Catheter Placement in Parturients With BMI ≥50 kg/m2

NCT05361512 | Completed

• 1 other identifier: 22-03
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The prevalence of obesity has increased worldwide, and the anesthetic care of patients with obesity remains a challenge for providers despite advances. Obesity during pregnancy is a risk factor for hypertensive disorders, gestational diabetes, emergency cesarean section and higher prevalence of difficult airway. Neuraxial techniques should always be preferred in women with obesity, particularly in those with body mass index (BMI) ≥50 kg/m2, where complications can be magnified. It is estimated an overall epidural failure rate of 4.3% in patients with obesity and an epidural failure rate of 13.7% in those with BMI ≥50 kg/m2. Hence, a confirmatory test of epidural catheter placement should prove useful in this patient population. The epidural electrical stimulation test (EEST) and the epidural waveform analysis are tests described in the literature as confirmatory methods for accuracy of placement of the epidural catheter. The Tsui test has been well studied in obstetric patients, including required threshold electric currents and muscle contraction patterns. However, these studies have been conducted in patients receiving lumbar epidural catheters. Furthermore, they have not specifically included women with obesity class 3, particularly those with BMI≥50 kg/m2. In a recent study conducted in our department, the investigators have observed that patients with BMI≥50 kg/m2 require placement of an epidural catheter at a low-thoracic or high lumbar interspace, to allow the provision of effective surgical anesthesia for cesarean delivery, which often requires a modified incision, either transverse supra-umbilical or infra-umbilical. There are only few studies with waveform confirmation in obstetric patients showing conflicting results and certainly no studies under the circumstances described above. Finally, the Tsui test and the epidural waveform analysis have never been compared in the obstetric population. The investigators aim to describe the characteristics of the Tsui test and of the epidural waveform analysis in parturients with BMI≥50 kg/m2 receiving epidural catheter placement at T12-L1 for both labor analgesia or anesthesia for cesarean delivery

Conditions

Labor Pain

Keywords

epidural catheter; epidural analgesia; cesarean section; Tsui test; epidural waveform

Outcome Measures

Primary Outcomes (2)

• Tsui test motor response: questionnaire

  Tsui test motor response will be recorded as either: left, right or bilateral. Any increase in current requirement after the test dose will be recorded.

  15 minutes

• epidural waveform test (catheter) - questionnaire

  A positive epidural waveform test through the catheter, defined as the presence of a pulsatile waveform observed in synchrony with heart rate: yes or no.

  15 minutes

Secondary Outcomes (7)

• epidural waveform test (needle) - questionnaire

  15 minutes

• Tsui test motor response (before test dose): questionnaire

  15 minutes

• Tsui test current threshold (baseline)

  15 minutes

• Tsui test current threshold (after test dose)

  15 minutes

• Laterality of the Tsui test: questionnaire

  15 minutes

Study Arms (1)

Patients having an epidural placed for labour analgesia or anesthesia for cesarean delivery

Patients with BMI\>=50 who are having an epidural placed may take part in this study.

Device: Tsui test; Device: epidural waveform analysis

Interventions

Tsui test DEVICE

The stimulator is set at frequency of 1Hz with 0.2 msec pulse width and the current output ranging from 0 to 20 mA. The current output will be carefully increased from zero until motor activity is detected up to a maximum of 20 mA.

Also known as: epidural electrical stimulation test (EEST)

Patients having an epidural placed for labour analgesia or anesthesia for cesarean delivery

epidural waveform analysis DEVICE

A pressurized 500ml normal saline bag will be connected to a pressure transducer kit and the transducer will be connected to a portable monitor with the scale set at 0-40 mmHg or to optimum scale. The transducer will be levelled with the heart approximated at the patient's manubrio-sternal angle, with the patient in the sitting position. Sterile tubing will be connected to the epidural needle and attached to transducer. The tubing connection will be filled with saline to ensure proper reflection of the pressure transducer tracing. Test will be considered positive in case of pulsatile waveform is observed in synchrony with heart rate.

Patients having an epidural placed for labour analgesia or anesthesia for cesarean delivery

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: female
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Parturients with BMI≥50 kg/m2 requesting epidural labor analgesia or undergoing elective cesarean delivery.

You may qualify if:

• \- Parturients with BMI≥50 kg/m2 requesting epidural labor analgesia or undergoing elective cesarean delivery

You may not qualify if:

• contraindication to epidural anesthesia
• allergy or hypersensitivity to lidocaine, bupivacaine or fentanyl
• those with implanted electronic devices.

Sponsors & Collaborators

• Samuel Lunenfeld Research Institute, Mount Sinai Hospital: lead

Study Sites (1)

Mount Sinai Hospital

Toronto, Ontario, M5G1X5, Canada

Location

MeSH Terms

Conditions

Labor Pain

Condition Hierarchy (Ancestors)

Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Jose Carvalho, MD

  MOUNT SINAI HOSPITAL

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 29, 2022
• First Posted: May 4, 2022
• Study Start: June 21, 2022
• Primary Completion: February 14, 2023
• Study Completion: February 14, 2023
• Last Updated: February 23, 2023

Record last verified: 2023-02

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)